Old board and chip revisions
FMMT666
Posts: 14
in Propeller 2
Greetings Propeller people,
I just found a bag with two dozen P2 CPUs, a P2 module Rev. A
board and one of this big eval boards with no revision label on it.
Ordered them immediately after they were available at Mouser
that time. Maybe around 2020 or so.
As far as I can see, the big one is now at rev. C and this
edge thingy now has a D printed on it.
Could anyone point me to the docs for my old revisions?
The website only has newer ones.
Is there anything important I need to know?
Also - and probably even more important, are there newer
versions of the CPU itself already? Or is the chip still up
to date and the newest one?
thx
Comments
Ok, well the very first batch of chips had some issues and aren’t supported that well anymore. They aren’t really that bad, main issue was adc crosstalk between pins. You would probably need to find a very old version of the parallax tools to use them. But, I think FlexProp can support them if you can figure out how to set the right flag.
But, as described, think better off to get new stuff…
The chips are a simpler situation …
The new document describes the changes from rev. A to rev.c
https://docs.google.com/document/u/0/d/1gn6oaT5Ib7CytvlZHacmrSbVBJsD9t_-kmvjd7nUR6o/mobilebasic
Read design status notes at the top .
The edge and eval boards are more nuanced.. think all edge boards are supported but newer ones have slight improvements.
As I recall the very first Eval boards, which were very few, with rev a chips, aren’t really supported by parallax but other tools will work.
I think Eval boards with rev.b chips are fine but just use more energy and maybe can’t overclock as well.
But really I think we all want to just put the first versions of the chips in rear view mirror. Think current rev is final.
Thanks!
Found a 2nd big eval board, rev. C with an LHU2019 marked chip.
Revision C, according to the doc. So at least one is up to date.
I did not manage to find the other two variants I have; they're
also not in the rev. A (silicon) doc:
Any idea what this could be?
EDIT:
Apparently week 20 and 42 of 2020, I guess.
So they are all revision C chips, right?
IRRC the rev B chips were sold in 4 packs direct from Parallax. If you bought from Mouser I think they would be rev C. I don't know if rev A chips were ever sold alone. Probably not. There are only 145 ? of those chips around.
My rev B eval board chip is P2X8C4M64PES datecode LPD1941.
My P2EDGE-32MB has P2X8C4M64PES LHU2019. So there are rev C chips marked as "engineering sample."
Yes, Rev A chips were special sample handouts from Chip himself. None of them sold commercially. They were only on Rev A Eval boards too I think. There actually is still online docs for them but yeah, not supported any longer.
Difference between Rev B and Rev C chips is just the removed pinB x1 gain ADC input select on Rev C to remove the crosstalk with pinA. Not even a ROM update as that was more cost compared to just a track cut on alternate I/O pins.
EDIT: There was notable changes between the Rev B and Rev C of the EC boards. I can't tell what was changed from Rev A to Rev B. C to D was just the voltage regulators changed due to Covid-19 shortages.
Product Guides - https://www.parallax.com/package/p2-edge-module-product-guide/
Schematics - https://www.parallax.com/package/p2-edge-module-schematics/
Great, thx!
So except for the Edge Module, mine does not even have
an SD-card slot, everything seems to be up to date.
I will unsolder the chip for further use. 20 bucks saved.
Just ordered one of these Rev. D, 32MB variants from Mouser.
Guess I have to refresh some old PASM skills for the P2 ...
PASM on P2 is great!
+1 to this!
If you used PASM on the P1, you're going to find PASM on the P2 -- as Ray indicated -- is really great.
I would not destroy the edge, it is a perfect working board, except no sd